A top Russian official has accusing a leading rating agency of trying to turn tycoons against the Kremlin.

Standard & Poor's earlier this week downgraded Russia's credit rating to a non-investment grade, for the first time in more than a decade.

In remarks in parliament on Friday, Deputy Prime Minister Igor Shuvalov said the goal of the downgrade was to push businesses "to withdraw their support" for the government and President Vladimir Putin.

The downgrade of Russia's sovereign debt is triggering a downgrade for Russian companies.

Russia has exceptionally low levels of public debts level for a country with a "junk" status but the downgrade underlined investors' fears about the unpredictability of Putin's foreign policy and the collapse of the ruble.